Lal said four doctors as well as nurses, medical technicians and others were involved in the scheme, working out of a house in Gurgaon with an operating theater.

Police also said they discovered a worldwide roster of 48 people waiting for transplants.

Kumar, who also uses the alias Dr. Santosh Rameshwar Raut, may not be in India anymore, police said.

Under Indian law, the sale of human organs is illegal, but the country has a flourishing black market. There have long been reports of poor Indians selling their kidneys and even giving them up by force in some cases.

The problem is extensive enough for the Indian Health Ministry to be developing new legislation that lawmakers hope will stop the illegal organ trade.

Shakil, a 28-year-old recovering from a transplant in a Gurgaon hospital, winced as he described how his kidney was forcibly removed.

"Two armed guards took me to another room. They took blood samples ... forced me onto a stretcher and then they gave me an injection," he said. "When I woke up, I had pain in my waist and I was dizzy."

Shakil and others in nearby hospital beds said a man approached them with promises of well-paying jobs. Instead, he brought them to the house in Gurgaon, they said.

"The surgery has been done professionally, there's no doubt, by someone who is qualified and seems to know his job," said Sanjay Narula, a surgeon who is caring for the victims now.E-mail to a friend